The Role of Calcium and Vitamin D in bone health
Guest: Dr. Diane Kamen – Rheumatology & Immunology
Host: Dr. Marcy Bolster – Rheumatology & Immunology
Welcome to an MUSC Podcast
Dr. Marcy Bolster: I’m Dr. Marcy Bolster. I’m a professor of Medicine in the Division of Rheumatology at the Medical University of South Carolina. I’m Medical Director for the Center for Osteoporosis and Bone Health at MUSC. Today, I’ll be speaking with Dr. Diane Kamen who is an assistant professor of Medicine in the Division of Rheumatology at MUSC. We’ll be discussing calcium and vitamin D supplementation in bone health and osteoporosis. Welcome, Dr. Kamen. Thank you for being here today.
Dr. Diane Kamen: Thank you. It’s my pleasure.
Dr. Marcy Bolster: Dr. Kamen, let’s start with the role of calcium and vitamin D supplementation in osteoporosis and bone health.
Dr. Diane Kamen: It’s coming to light that people, from an early age, are not getting adequate calcium or vitamin D, putting them at risk for low bone strength and an increased risk of fractures later in life. We always hear about milk and getting plenty of calcium in childhood, but vitamin D deficiency is something we’re hearing more about; we’re discovering a high prevalence of vitamin D deficiency in people here in the United States. We don’t get it as much from the food we eat as we do from sunlight and taking supplements of vitamin D.
Dr. Marcy Bolster: So, it’s important, even for children and adolescents, to have enough calcium and vitamin D. I’m hearing you say that calcium and vitamin D are very important during childhood and adolescence. When is it that people achieve peak bone mass?
Dr. Diane Kamen: When we look at bone density, we usually consider a woman in her twenties as reaching her peak bone density. Then, certainly, at menopause, as estrogen levels drop off, bone density starts to decrease. Reaching high enough peak bone density, really, is so important. The higher you are before you start dropping, the longer it will take to get to osteoporosis or an increased risk of fracture.
Dr. Marcy Bolster: So, what is the role of vitamin D in the body? What is its impact?
Dr. Diane Kamen: Vitamin D plays a big role in the body. It’s a hormone. In addition to being called vitamin D, it’s a hormone, in the sense that it plays a big role in over 900 different functions in the body. In addition to helping us absorb more calcium, it plays into the bones ability to hold onto important minerals and nutrients. It also acts on cells of the immune system to help us fight off certain types of infections. We believe it also plays a role, and this is something we’re researching here at MUSC, in the body’s ability to maintain a sense of tolerance to self in preventing autoimmune disease. And that’s something that may occur even in utero and early childhood, as well as throughout our lives.
Clearly, we know it’s important around menopause in making sure that calcium and vitamin D are maximized. That’s why we’re really pushing education early in life to make sure young kids are getting enough calcium and vitamin D. It may be that vitamin D is playing a role early in life as well.
Dr. Marcy Bolster: So, if you were going to list the things that would make a patient, or person, more susceptible to having a vitamin D deficiency, what would those four or five things be?
Dr. Diane Kamen: Well, the most common reason would be inadequate conversion from the sun in the skin, whether that’s from being inside during the day, wearing sunblock, having darker skin, being older aged; as we age, the skin doesn’t convert as well. The sun helps us make vitamin D, and for various reasons, people might not get enough vitamin D from sunlight exposure.
Kidney disease is another factor. We convert the vitamin D to its active form, which is a hormone in the body. The kidneys perform that function. So, anyone with kidney disease, whether it’s from high blood pressure, diabetes, autoimmune diseases, we have to look more closely at that vitamin D level. Low vitamin D can contribute to things like high parathyroid hormone levels, which then feed back into bone disease and low bone density. So, it’s all sort of a vicious cycle. If we can get the vitamin D levels up, we’d at least be counteracting part of that vicious cycle that, in the end, affects the bones.
Dr. Marcy Bolster: It sounds like vitamin D has a lot of essential functions in the body, not just in terms of bone. One other question, do you have any comments on the role of vitamin D in terms of osteoporosis and fractures?
Dr. Diane Kamen: There’ve been studies looking at medications that we know for a fact help prevent fractures, things like bisphosphonates, which we use very commonly with people with low bone density. If vitamin D and calcium are maximized, that helps even more. So, it seems to work in conjunction with other medications to help prevent fracture down the road.
There been other studies looking purely at calcium and vitamin D in preventing fracture. Clearly, that plays a role as well. Some of the problems with past studies of vitamin D have been that we didn’t know we needed that much. The limitations of the studies were that most of the study participants did not get adequate levels of vitamin D. The trials going on now have a much higher goal as far as vitamin D intake.
Dr. Marcy Bolster: Do you have any comment on whether or not any person should decide on their own to take calcium and vitamin D?
Dr. Diane Kamen: I think it’s probably a good idea to have a discussion with your primary care doctor, who would be aware of the benefits and potential risks of calcium and vitamin D. There are people that are at higher risk of having kidney stones from high calcium levels in the blood and urine. We recommend that people run through the potential risks and benefits with their physician before starting on a self treatment plan. With this being available over the counter, it does make it easier, of course, for people to get supplements.
Dr. Marcy Bolster: Dr. Kamen, thank you very much for being here today. This has been very informative.
Dr. Diane Kamen: Thank you, Dr. Bolster, my pleasure.
Thank you for listening to the information about the Center for Osteoporosis and Bone Health at the Medical University of South Carolina. In order to get an appointment, patients may self-refer or they may be referred by their physician. The scheduling number is (843) 876-2663 (876-BONE.) I hope this information is helpful to you.
Dr. Marcy Bolster, the Medical Director for the Center for Osteoporosis and Bone Health, talks with Dr. Diana Kamen, an assistant professor of Medicine in the Division of Rheumatology at MUSC. They discuss the importance of vitamin D and Calcium to build strong bones, the daily amounts a person should consume, as well as the advantages or disadvantages of taking supplements.